Definition of Ultrasound

Ultrasound: High-frequency sound waves. Ultra-sound waves can be bounced off tissues by using special devices. The echoes are then converted into a picture called a sonogram. Ultrasound imaging allows an inside view of soft tissues and body cavities without the use of invasive techniques. Ultrasound is often used to examine a fetus during pregnancy. There is no evidence that any danger occurs from ultrasound during pregnancy.